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Published October 04, 2012, 12:00 AM

ENERGY: Freedom’s Frontier digs in

Additional dragline at lignite mine allows access to deeper coal

By: Kris Bevill, Prairie Business Magazine

In July, Beulah-N.D.-based Coteau Properties Co. welcomed a new dragline into operation at the nation’s largest lignite coal mine, Freedom Mine, north of Beulah. The 13-million-pound Bucyrus Erie Model 2570 walking dragline, dubbed Freedom’s Frontier, had been purchased in 2003 but sat unassembled for several years, patiently waiting to be called into duty when the need to access deeper seams of coal required its use. And now its time has come.

Coteau Properties, a subsidiary of Texas’ North American Coal Corp., has operated the mine since 1983 and supplies 15 million tons of coal annually to Basin Electric Power Cooperative’s Dakota Coal Co., which in turn markets the product to several North Dakota power plants as well as to the Great Plains Synfuels Plant in Beulah. Ultimately, those 15 million tons of coal produce a combined 1,600 megawatts of electricity each year as well as natural gas and other products. Prior to July, two draglines identical to Freedom’s Frontier had been able to efficiently move the massive amounts of clay material at the mine — known as overburden in the mining industry — to access the coal that rests below, but shallower seams of coal have been mined through over the past two decades and additional equipment has become necessary in order to efficiently mine deeper sources of coal.

“We’re getting to a point in time where demand from Dakota Coal is still at 15 million tons but the amount of overburden is growing, so we’ve got to move more earth to get the same number of tons out of the ground,” says David Straley, manager of government and public affairs at North American Coal. “By far, when you look at the number of yards that we move, the best and easiest option is the dragline.”

Each of Coteau Properties’ draglines can scoop up 150 tons of earth per minute in massive buckets that hold the equivalent of four 4-wheel drive Suburbans. Without Freedom’s Frontier, Coteau would need to employ a truck and shovel fleet or some other type of moving equipment to remove the additional overburden, but that option wouldn’t be as economical, Straley says. He declined to release the cost of the Frontier, which is not a new model and was previously used at a coal mine in Illinois, but says new draglines could cost as much as $180 million. The two draglines already in use at Freedom Mine were purchased for $40 million each in the 1970s, according to Coteau Properties.

Even though shallow seams of coal have been mined through, Freedom Mine is far from being depleted of its lignite. According to Coteau Properties, North Dakota is estimated to have enough lignite to last 800 years at the current rate of use. The current 15 million-ton-per-year supply contract with Dakota Coal runs through 2035 and the addition of Freedom’s Frontier will allow Coteau Properties to meet that demand at the best cost, Straley says. Life of mine plans offer an indication of how deep the coal will be 25 years from now and Straley assures it won’t be a situation where deeper digging is continuously required to meet supply demands. “Even though it’s deeper than it was in the past few years, it’s not going to be so deep that it will make it uneconomical to mine,” he says. “We’ve got access to coal for as long as they would ever want.”

Fifteen new employees were hired in direct relation to the commissioning of Freedom’s Frontier. Coteau Properties entire staff includes nearly 400 employees. PB

Kris Bevill

Editor, Prairie Business